JPH05109863A - Mechanical interface device - Google Patents

Abstract

PURPOSE:To obtain a seal sandwiching and pressing force without exerting a large load on a mounting case and to reduce the load capacity of a device for cassette raising and lowering by a method wherein a pressure force which is used to strongly sandwich and press a sealing material between a port door and a port plate is obtained from a port-door pushing-up mechanism. CONSTITUTION:When a wafer cassette 20 is conveyed onto a port door 31, an ascending and descending device 30 is raised and an ascending and descending stand 30A is raised. Then, a cylinder 301 is driven, a rod 302 is extended toward a cam face 311 at the port door 31, and a roller 303 comes into contact with the cam face 311 and presses the cam face 311 while the rod 302 is being extended further. Thereby, a component force toward the upper part of the port door 31 acts. The port door 31 is pushed up to the rear surface of a port plate 3; it is levitated from a table 30A; it strongly sandwiches and presses a sealing material 15 between itself and the port plate 3. Consequently, it is sufficient that the ascending and descending device 30 is provided with a load capacity which is sufficient to raise and lower the port door 31 and the wafer cassette 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mechanical interface device used in a semiconductor manufacturing process.

[0002]

2. Description of the Related Art Conventionally, semiconductor processing has been carried out in a specially designed clean room in order to prevent particle contamination of the semiconductor, but there is a problem that it is too expensive including maintenance. Since there is a limit to the reduction of the contamination level of particle contamination, for example, Japanese Patent Laid-Open No.
A standardized mechanical interface device has been developed, such as that disclosed in 0-143623.

This device is, for example, as shown in FIG.
The wafer processing apparatus (not shown) is housed and includes a main body case 1 of the apparatus filled with clean air, a portable type box (hereinafter referred to as a pod POD) 10 and a transfer apparatus 30. Top plate 2 of the body case 1 of the device body
The port plate 3 allows the port (wafer cassette 2
0 carry-in / carry-out port 4 is formed, and the grip portion 10A is formed.
The pod POD 10 having the above is mounted on the port plate 3. The pod POD 10 has a shape having a flange 12 having an annular portion 12 a around the opening 11. The transfer device 30 in this example is an elevating device, and the wafer cassette 20 is placed on an elevating table 31 supported by an elevating shaft 32 to elevate and lower. , The port plate 3 is abutted or fitted from below to seal the port 4 to the outside of the main body case 1, and the base 21 of the wafer cassette 20 on the port door 31 surrounds the opening 11 of the pod POD 10. The opening 11 is sealed by abutting the part. Hereinafter, this stand 21 will be referred to as a pod door. Reference numeral 13 is a sealing material, which seals between the opening of the pod POD 10 and the pod door 21, sealing material 14 seals between the flange 12 of the pod POD 10 and the port plate 3, and sealing material 15 seals with the port plate 3. The space between the port door 31 is sealed.
Reference numeral 40 denotes a lock mechanism having a lock lever 41 driven by a geared motor (not shown),
It works to push down the flange 12 of D10 onto the port plate 3.

In this example, after the unprocessed wafer W is transferred onto the port door 31 from another location (not shown), the pod POD 10 is mounted on the port plate 3 and
Fix with the lock lever 41. After fixing with the lock lever 41, supply clean air into the pod POD10,
After making the inside of the pod POD10 a clean atmosphere similar to the inside of the main body case 1, the port door 31 is lowered to the transfer position. When the port door 31 descends to the transfer position, the transfer device (not shown) moves the wafer cassette 20 on the port door 31.
To the processing machine.

[0005]

Conventionally, the particle contamination of the wafer W has been a problem. However, as the density of semiconductor integrated circuits has increased, the influence of a natural oxide film on the wafer surface due to oxygen in the air has become a problem. In order to prevent the growth of this natural oxide film, it becomes necessary to move and transfer the wafer W in an inert gas (N ₂ gas) atmosphere. Currently, the concentration of O ₂ is 10 ppm or less, An N ₂ gas atmosphere having a H ₂ O concentration of 100 ppm or less is required.

[0006] When using the apparatus described above, sets the air in the main body case 1 and N ₂ gas atmosphere was replaced with N ₂ gas, pod POD10 is the pod POD10 is on the top plate 2 of the casing 1 Each time it is done, N
_The atmosphere is replaced with ₂ gas to provide an N ₂ gas atmosphere.

FIG. 6 shows an example of a mechanical interface device having this gas replacement function. The pod door 21 incorporates fixing means as shown in FIG. Be transported to.

In FIG. 7, the pod door 21 is a hollow frame. Reference numeral 61 is a cam, and a cam shaft (not shown) extends into the port door 31 and is driven by a motor (not shown) housed in the port door 31. Reference numeral 62 denotes a plate-shaped lock arm having a rolling element 62a, which is supported by a cantilever so as to be capable of advancing and retracting in the longitudinal direction and tilting. 6
3 is a fulcrum member, and 64 is a spring. 10B is a pod PO
It is a fitting recess formed on the inner peripheral surface of the flange 12 of D10.

In this structure, the cam 61 has a special cam surface, and when the cam 61 rotates, the lock arm 62 is displaced toward the engaging recess 10B in the direction of the arrow in the figure, and the tip end thereof is fitted into the fitting recess 10B. Engage with.

Now, it is assumed that the pod POD 10 is transferred from another place onto the port plate 3 and the inside is in a clean air atmosphere. In this state, the opening 1 of the pod POD10
The seal material 13 is provided between the pod P1 and the pod door 21.
The sealing material 14 is provided between the flange 12 of the OD 10 and the port plate 3, and the port plate 3 and the port door 31 are also provided.
A sealing material 15 is provided to seal the gap between and. At this time, the lock arm 62 engages with the engagement recess 10B and tilts to press the pod POD 10 toward the port plate 3 to ensure the sealing property between the flange 12 and the port plate 3.

When the inside of the pod POD10 is replaced with N ₂ gas, after the lock by the lock arm 62 is released, the elevating shaft 32 is slightly lowered to separate the pod door 21 from the opening surface of the pod POD10, and the gas supply port is opened. Three
A and the space where the gas exhaust port 3B is open (the space between the port 4 and the peripheral side surface of the port door 31) A is the pod POD
Communicate with the inside of 10. In fact, the pod POD10 is placed in the port plate 3, N ₂ supply side valve connected to the gas cylinder V1, opening the exhaust valve V2, N ₂ gas into the space A from the gas supply port 3A Press-fit,
Dust and the like adhering to the surfaces of the pod door 21 and the port door 31 exposed to the outside air are discharged from the gas exhaust port 3B to the outside of the apparatus. Therefore, as described above, when the pod door 21 is lowered integrally with the port door 31 so that the space A communicates with the inside of the pod POD 10, the N ₂ gas delivered from the air supply side valve V1 through the gas air supply port 3A. Is pod P
The air in the pod POD10 that has entered the OD10 is discharged from the gas exhaust port 3B to the outside of the apparatus, and the inside of the pod POD10 is replaced with N ₂ gas. When the raising / lowering shaft 32 is lowered as described above, the flange portion 31A of the port door 31 is moved to the port plate 3
The space A is separated from the lower surface of the pod POD1.
Not only communicates with the inside of 0, but also inside the body case 1 (already
N ₂ has a gas atmosphere) both communicating, POD10
Since the air inside may enter the inside of the body case 1, in this example, the bellows 50 is provided to prevent this.

By the way, the sealing material 15 is sandwiched between the port door 21 and the port plate 3 by the pressing force of the port door 21 to secure the sealing property. Ring) has variations in manufacturing, and when viewed macroscopically, there is also a wavy shape on a clean plane, so the sealing material 15 is crushed with a strong force in order to ensure sufficient sealing performance. It is necessary to provide the lifting device 30 with a force for crushing the sealing material 15 in addition to the lifting force of the wafer cassette 20, and the lifting device 30 originally has a sufficient load capacity of about 10 kgf. It is uneconomical to use a 100 kg class product, and the equipment case that receives the reaction force must have a rigid body that can withstand the strength. Thickness is thick, there is also a problem that the weight reduction.

The present invention has been made in order to solve this problem. It is possible to obtain a seal clamping pressure without imposing a heavy load on the device case, and to significantly reduce the load capacity of the cassette lifting device. An object of the present invention is to provide a mechanical interface device device that can be used.

[0014]

In order to achieve the above object, the present invention, in claim 1, is transferred onto a port plate which is provided in a main body case and forms a port for loading and unloading an object to be processed. A flanged pod that covers the port, a pod door that can airtightly close the opening of the pod, a port door that can be airtightly closed from the bottom by engaging a port plate, and a port door that is provided in the main body case. A mechanical interface device that includes a lifting device that moves up and down, and a means that biases the flange of the pod toward the port plate, and the port door conveys the pod door from the inside of the pod to the body case and vice versa. In the main body case, a plurality of port door push-up mechanisms having movable rods are provided, and the lifting device includes the port doors. A movable table having a lift table that is displaceable in one direction, and the movable rods of the port door lifting mechanism are engaged with a port door on the lift table that has been raised to a predetermined height to urge the port door upward. did.

According to a second aspect of the present invention, the port door is formed with a cam surface having a corner drop at the lower portion of the peripheral surface thereof, and the movable rod of the port door pushing-up mechanism is a horizontally oriented cylinder rod that moves forward and backward with respect to the cam surface. A trochanter is provided at the tip of the rod.

In the third aspect, the port door positioning mechanism is provided on the lift table.

According to a fourth aspect of the present invention, the positioning mechanism is a pin and a pin hole into which the pin can be engaged, and both are engaged with each other through an elastic member.

According to a fifth aspect of the present invention, the port door has a concave portion on the lower surface of which the elevator can be loosely fitted, and the positioning mechanism is a rotator supported by the elevator and engageable with the peripheral surface of the recess. And

[0019]

In the present invention, the pressing force for strongly pinching the sealing material between the port door and the port plate is obtained not from the lifting device but from the port door lifting mechanism. , Wafer cassette 2
It suffices if there is sufficient load capacity to raise or lower 0.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, the port door 31 is provided separately from the elevating device 30, and the elevating device 30 has an elevating table 30A for mounting the port door 31 attached to the elevating shaft 32. Positioning pins 30a are provided on the upper surface of the lift table 30A so as to vertically project.

A cam surface 311 is formed on the lower portion of the peripheral surface of the flange 31A of the port door 31 in this embodiment, and a pin hole 312 is formed on the lower surface thereof to form a positioning mechanism by engaging with the positioning pin 30a. An elastic ring 313 is fitted on the inner peripheral surface of the pin hole 312. The port plate 3 has a flange 3 of the port door 31 on its lower surface.
An annular base 300 capable of receiving 1A is extended, and a port door pushing mechanism (in this embodiment,
The cylinder) 301 is firmly fixed. A plurality of cylinders 301 are provided at predetermined intervals in the circumferential direction.

A trochanter 303 is provided at the tip of the rod 302 of the cylinder 301, and the rod 302 is driven to move back and forth inward in the radial direction. Also, the lifting device 30
The highest position of the elevator 30A is defined as one predetermined position.

The pod POD10 of this embodiment is a magnetic material (made of magnetic stainless steel), and the flange 12 thereof is an extension flange 12A which further extends outward from the annular portion 12a.
It is a wide flange formed with. The annular portion (hereinafter, indicated by reference numeral 12b) of this embodiment is a fitting tubular portion (a fitting tubular portion for positioning), and the pod POD10 is
The annular portion 12b is fitted in the port plate 3 and placed on the port plate 3, and the pod door 21 is fitted in the annular portion 12b. The tip of the fitting tubular portion 12b has a rounded shape. In the portion of the surface of the port plate 3 facing the extension flange 12A, circumferentially extending seal grooves 3a and 3b are formed at a small interval in a direction orthogonal to the circumferential direction. Sealing materials (O-rings) 51a and 51b are fitted in the sealing grooves 3a and 3b, and both sealing materials form an annular groove-shaped space A on the surface of the port plate. The port plate 3 is further formed with a passage hole 3C having one end opening to the surface of the port plate 3 from between the seal grooves 3a and 3b and the other end opening to the outer surface of the port plate 3 and a gas hole. An air supply port 3A and a gas exhaust port 3B are formed. A pipe 52 is provided in this passage hole 3C.
This is connected to a vacuum pump 60 disposed outside the main body case 52.

Reference numeral 53 is a permanent magnet, which is embedded in a portion of the surface of the port plate 3 facing the extension flange 12A.
Are arranged at a predetermined interval in the circumferential direction.

The gas inlet 3A and the gas outlet 3B are used for replacing the inside of the pod POD10 with N ₂ gas, and the gas inlet 3A is connected to an N ₂ gas cylinder (not shown) through a pipe. It Further, the inside of the main body case 1 is in an N ₂ gas atmosphere and is constantly pressurized by injecting 20 L / min of N ₂ gas.

In this embodiment, when the pod POD 10 is transferred from the outside of the apparatus onto the port plate 3 of the main body case 1, the groove-shaped space A formed by both seal members 51a and 51b is closed by the lower surface of the extension flange 12A. To be done. At this time, the port door 31 is pushed up toward the port plate 3 by the component force of the pushing force received by the cam surface 311 from the trochanter 303 side, and is pushed up toward the port plate 3 to pinch the sealing material 15 between the port door 31 and the port plate 3. The door 31 and the port plate 3 are hermetically sealed.

In this state, when the transfer of the pod POD 10 is completed, the vacuum pump 60 is driven. When the vacuum pump 60 is driven, the inside of the pipe 52 has a negative pressure. Therefore, the air in the closed groove space A is exhausted to the outside through the pipe 52, and the groove space A has a negative pressure. When the groove-shaped space A has a negative pressure, a suction force acts on the flange 12 of the pod POD10, so that the flange 12 of the pod POD10 resists the elasticity of the seal materials 51a and 51b and the port plate 3 is pressed.
The sealing material 51
A and 51b are clamped.

As described above, in general, the sealing material (O-ring) has variations in manufacturing, and when viewed macroscopically, there is also a corrugated shape on a clean plane. When placed on the port plate 3, there is no guarantee that both seal members 51a and 51b are in contact with the surface of the flange 12 over the entire circumference thereof, and it is overlooked that there is a non-contact engagement part. Therefore, when the above-mentioned vacuum suction is performed, a sufficient vacuum suction force cannot be obtained.

However, in this embodiment, the port plate 3
Since the permanent magnet 53 is disposed in the pod POD10 and the pod POD10 is a magnetic body, the flange 12 of the pod POD10 receives the magnetic attraction force and presses the sealing materials 51a and 51b. Since a large number of permanent magnets 53 are lined up in the circumferential direction of the port plate 3, the magnetic attraction force is generated by the flange 12 of the pod POD 10.
Acts on the entire circumference of.

Therefore, in this embodiment, the pod POD 10
Pod POD10 when placed on the port plate 3
Since the magnetic attraction force acts on the flange 12 of the above and presses the sealing materials 51a and 51b over the entire circumference, the groove-shaped space A
Becomes a sufficiently sealed space, and by the above vacuum suction,
Not only the sealing materials 51a and 51b, but also the sealing material 13 is surely firmly pressed around the entire circumference to secure good sealing performance.

When the seal between the flange 12 of the pod POD 10 and the port plate 3 is secured in this manner, the cylinder 301 is driven to retract and the rod 302 moves outward in the radial direction of the base 300. Along with this, the port door 31 descends onto the table 30A, and the trochanter 30
When the engagement between the cam surface 311 and the cam surface 311 is disengaged, the port door 31 is placed on the lift table 30A as shown in FIG.

When the port door 31 is placed on the lift table 30A, the lift device 30 starts the lowering operation, and the wafer cassette 2
0 is taken into the main body case 1 and is carried from the port door 31 to the surface treatment apparatus side such as a reaction furnace by a carrying means (not shown). Wafer cassette 2 for processed wafers
0 is transported to the port door 31 on the lift table 30A by the transporting means (not shown). When the wafer cassette 20 is transferred onto the port door 31, the lifting device 30 performs a lifting operation, and the lifting platform 30A is lifted to a predetermined height shown in FIGS. When the lifting platform 30A rises to a fixed position,
The cylinder 301 is driven so that the rod 302 extends toward the cam surface 311 of the port door 31, and the cam surface 311
The trochanter 303 comes into contact with the rod 302, and the rod 302 further extends,
Press the cam surface 311. As a result, a component force directed to the upper side of the port door 301 acts, the port door 31 is pushed up to the lower surface of the port plate 3 and floats up from the table 30A, and as shown in FIG. Apply a strong pressure between.

In this way, the sealing material 15 is attached to the port door 3
1 is configured to obtain a pressing force for strongly sandwiching between the port plate 3 and the port plate 3 from the cylinder 301. Therefore, the elevating device 30 only needs to have a sufficient load capacity for elevating the port door 31 and the wafer cassette 20. become.

Therefore, it is not necessary to consider the reaction force exerted on the device case 1 of the elevating device 30, and the device case 1 does not need to have a large rigidity as conventionally required.

The positioning pin 30a and the pin hole 31
The elastic ring 313 is provided between the pin 30a and the pin 2 in order to prevent generation of friction powder due to direct friction between the pin 30a and the pin hole 312.

FIG. 3 shows another embodiment of the present invention. The cylinder of the port door pushing-up mechanism 300 is a twist cylinder, and the rotating arm 304 connected to the expanding and contracting rod of the port door 31 is the port door 31. Engage the lower surface of the. In addition, the port door 31 has an elevator 30A on its lower surface.
Is formed with a recess 314 that can be loosely fitted, and a plurality of positioning rollers 315 that engage with the inner peripheral surface of the recess 314 are provided on the peripheral surface of the lift table 30A.

In this embodiment, when the pod POD 10 is transferred onto the port plate 3 of the main body case 1 from the outside of the apparatus, the port door 31 receives a pushing force upward from the rotating arm 304 to cause the port plate 3 to move. Is pushed up toward, pinching the sealing material 15 with the port plate 3,
The port door 31 and the port plate 3 are hermetically sealed.

Then, as described above, the pod POD1
When the seal between the flange 12 of 0 and the port plate 3 is secured, the cylinder 301 is driven to retract and the movable arm 304 is rotated to the retracted position shown in FIG. 4, and accordingly, the port door 31 is moved to the table 30A. The port door 31 is lowered, and the port door 31 is placed on the lifting platform 30A.

[0040]

As described above, according to the present invention, the port door pushing-up mechanism is provided, and the pushing force for strongly pinching the sealing material between the port door and the port plate is raised not by the lifting device but by the port door pushing-up mechanism. Since the structure is obtained from the mechanism, the lifting device only needs to have a sufficient load capacity to lift and lower the port door and the wafer cassette, and it is not necessary to consider the reaction force exerted on the device case by the lifting device. Eliminates the need for high rigidity as has been conventionally required.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a vertical sectional view for explaining the operation of the above embodiment.

FIG. 3 is a vertical sectional view showing another embodiment of the present invention.

FIG. 4 is a vertical sectional view for explaining the operation of the other embodiment.

FIG. 5 is a diagram showing a conventional mechanical interface device.

FIG. 6 is a diagram schematically showing another example of a conventional mechanical interface device.

7 is a vertical cross-sectional view of the pod door in the conventional example of FIG.

[Explanation of symbols]

 1 Main Body Case 3 Port Plate 3a, 3b Seal Groove 3A Air Supply Port 3B Exhaust Port 3C Passage Hole 4 Port 10 Pod POD 11 Pod POD Opening 12 Pod POD Flange 12A Extension Flange 12b Annular Portion 13, 14, 15 Sealing Material 20 Wafer cassette 21 Pod door 30 Lifting device 30A Lifting table 30a Positioning pin 31 Port door 31A Port door flange 32 Lifting shaft 51a, 51b Sealing material 52 Piping 53 Permanent magnet 60 Vacuum pump 300 Stand 301 Cylinder 302 Rod 303 Roller 311 Cam Surface 312 pin hole 313 elastic ring 314 recess 315 trochanter A grooved space

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuhiro Hayashi, 100 Takegahana-cho, Ise-shi, Mie Shinko Electric Co., Ltd. (ISE) Tetsuhei Yamashita 100, Takegahana-cho, Ise-shi, Mie Shinko Electric Co., Ltd. (72) Inventor, Makoto Murata, 100, Takegahana-cho, Ise-shi, Mie Shinko Electric Co., Ltd., Ise Works (72) Inventor, Miki Tanaka, 100, Takegahana-cho, Ise-shi, Mie Shinko Electric Co., Ltd. (72) Inventor Moriya Hiya 100, Takegahana Town, Ise City, Mie Prefecture Shinko Electric Co., Ltd.

Claims (5)

[Claims] 1. A device provided on the main body case for carrying in an object to be processed,
A flanged pod that is transferred onto a port plate that forms an export port and covers the port, a pod door that can hermetically close the opening of the pod, and a port plate that can hermetically close the port from below Port door,
An elevating device provided in the body case for raising and lowering the port door, and means for urging the flange of the pod toward the port plate, the port door moving the pod door from the inside of the pod to the body case. In a mechanical interface device for carrying back and forth, a plurality of port door pushing-up mechanisms having movable rods are provided in the main body case, and the lifting device includes a lifting platform that holds the port doors so that they can be displaced upward. A mechanical interface device, wherein each of the movable rods of the port door pushing-up mechanism is engaged with a port door on a lift table that is raised to a predetermined height to bias the port door toward the port. 2. The port door has a cam surface in the shape of a corner drop formed on the lower portion of the peripheral surface thereof, and the movable rod of the port door pushing-up mechanism is a horizontally oriented cylinder rod that moves forward and backward with respect to the cam surface. The mechanical interface device according to claim 1, further comprising a trochanter. 3. The mechanical interface device according to claim 1, wherein the lift includes a port door positioning mechanism. 4. The mechanical interface device according to claim 3, wherein the positioning mechanism is a pin and a pin hole with which the pin can be engaged, and both of them engage with each other through an elastic member. 5. The port door has a recess on the lower surface thereof into which the elevator can be loosely fitted, and the positioning mechanism is a trochanter supported by the elevator and engageable with the peripheral surface of the recess. The mechanical interface device according to claim 3.